Make parsing function public.

libab already provides a _run_tree ... you can't run_tree if there's
no tree.

include/libabacus.h

@@ -232,6 +232,13 @@ void libab_get_false_value(libab* ab, libab_ref* into);
  */
 void libab_get_bool_value(libab* ab, int val, libab_ref* into);
 
+/**
+ * Parses the given piece of code using the given libabacus instance.
+ * @param ab the instance to use to parse the code.
+ * @param string the source code to parse.
+ * @param into the value to store the newly parsed tree into.
+ */
+libab_result libab_parse(libab* ab, const char* string, libab_tree** into);
 /**
  * Executes the given string of code.
  * @param ab the libabacus instance to use for executing code.

src/libabacus.c

@@ -406,7 +406,7 @@ void libab_get_bool_value(libab* ab, int val, libab_ref* into) {
     val ? libab_get_true_value(ab, into) : libab_get_false_value(ab, into);
 }
 
-libab_result _create_tree(libab* ab, const char* string, libab_tree** into) {
+libab_result libab_parse(libab* ab, const char* string, libab_tree** into) {
     libab_result result = LIBAB_SUCCESS;
     ll tokens;
 
@@ -442,7 +442,7 @@ libab_result libab_run(libab* ab, const char* string, libab_ref* value) {
     libab_tree* root;
 
     libab_ref_null(value);
-    result = _create_tree(ab, string, &root);
+    result = libab_parse(ab, string, &root);
 
     if (result == LIBAB_SUCCESS) {
         libab_ref_free(value);
@@ -483,7 +483,7 @@ libab_result libab_run_scoped(libab* ab, const char* string, libab_ref* scope, l
     libab_tree* root;
 
     libab_ref_null(into);
-    result = _create_tree(ab, string, &root);
+    result = libab_parse(ab, string, &root);
     if(result == LIBAB_SUCCESS) {
         libab_ref_free(into);
         result = libab_interpreter_run(&ab->intr, root, scope, SCOPE_NONE, into);

src/parser.c

@@ -525,6 +525,7 @@ libab_result _parse_fun(struct parser_state* state, libab_tree** store_into) {
     libab_result result = LIBAB_SUCCESS;
     int is_parenth, is_comma;
     libab_tree* temp;
+    *store_into = NULL;
     result = _parser_consume_type(state, TOKEN_KW_FUN);
     if (result == LIBAB_SUCCESS) {
         if (_parser_is_type(state, TOKEN_ID)) {